Social Difference Between Men and Women in Exposing Body Parts
That's a socially sanctioned way for female to display their crotch. It's done as routine in any sort of performance art by female (dance, gymnastic, figure skating, synchronized swimming, cheer leader, …). Often, the crotch display is prolonged, and as wide as possible.
We watch it, we score it, but we avoid thinking of it as crotch display.